The most interesting thing you'll watch today is this video about the geographic border between Canada and the ol' U.S. of A. Yes, really.

In his latest video, the always-entertaining C.G.P. Grey expounds on the northern hemisphere's 49th parallel – the circle of latitude that ostensibly separates America from the Great White North. But as Grey explains, the parallel's application as a strict, undeviating and linear international border has proven to be precisely none of these things.

Sez Grey:

While these sister nations get along fairly well, they both want to make it really clear whose side of the continent is whose. And they've done this by carving a 20-foot wide space along the border. All five and a half thousand miles of it.

With the exception of the rare New England town that predates national borders or the odd airport that needed extending, this space is the no-touching-zone between the countries and they're super serious about keeping it clear. It matters not if the no-touching-zone runs through hundreds of miles of virtually uninhabited Alaskan / Yukon wilderness. Those border trees will not stand.

Which might make you think this must be the longest, straightest deforested place in the world, but it isn't. Deforested? Yes. But straight? Not at all.

It only gets crazier from there. Trust us, this is one you want to watch all the way through.